What is the main reason for always cutting a crown in the road?

The main reason for always cutting a crown in the road is to effectively drain surface water. A crowned road design has a peak in the center that slopes down on either side, allowing rainwater or melting snow to flow off the road surface rather than pooling in low spots. This drainage is crucial as it helps to prevent water accumulation, which can lead to road damage, erosion, and safety hazards for drivers. Proper drainage ensures that the road maintains its structural integrity and extends its lifespan.

Improving appearance, reducing maintenance, and increasing traction are also considerations in road design; however, they are not the primary function of creating a crown in the roadway. At its core, the crown is fundamentally about managing surface water to enhance safety and preserve the road's condition over time.